In the factory automation control and LXI (LAN eXtension Instrument), the precision time synchronization has to be achieved. In the factory automation control (such as the manufacturing apparatus automation control or the robot arm automation control), in which the precision time synchronization is emphasized, the highest request on the communication time synchronization is the motion control, such as the robot arm control, the motor rotating speed control or the like. The node, such as the robot arm or the motor, and the grand master need to be time synchronized to each other. If the time synchronization is not precise, the product may fail, and the profit is directly influenced and the great loss in the money is caused.
The intranet measurement is adapted to the environment, such as the vehicle automation test production line, the airplane electronic apparatus test, the rocket launching base, or the like. Among these environments, computers, machines and sensing members have to be time synchronized so that the signals returned from the sensing members may be simultaneously measured at the specific time for subsequent data analysis.
The precision time protocol (PTP) may be adopted in the time synchronization of the network. The PTP specifies the best master clock (BMC) algorithm to determine which one node becomes the unique grand master in this network. In this network, all the slave nodes have to be time synchronized with the grand master. The grand master periodically (e.g., every two seconds) requests all slave nodes to be time synchronization for keeping time synchronization.
At present, in the time synchronization process, the slave node has to support the BMC algorithm to determine which is the best clock. In addition, in order to satisfy PTP, the slave node must have an operation system, a microprocessor, a driving device so as to calculate the time deviation between the slave node and the master node. In addition, the slave node still needs to consider the packet sending delay time in time adjustment.